Law of motion

Newton's First Law of Motion

Every object remains in a state of rest or of uniform motion in a straight line unless acted upon by an outside force." (An outside force is a net force.) ¬An object at rest will stay at rest, forever, as long as nothing pushes or pulls on it. An object in motion will stay in motion, traveling in a straight line, forever, until something pushes or pulls on it.

inertia

It is that property of matter which opposes changes in velocity. Inertia is the resistance to changes in motion. Inertia is proportional to mass. Big masses resist changing their motion more than smaller masses.

Newton's Second Law of Motion

Newton's Second Law of Motion defines the relationship between acceleration, force, and mass. force and acceleration are directly proportional, while mass and acceleration are inversely proportional. ¬When a force acts on an object, the object accelerates in the direction of the force. If the mass of an object is held constant, increasing force will increase acceleration. If the force on an object remains constant, increasing mass will decrease acceleration.

Newton's Third Law

When one object exerts a force on a second object, the second object also exerts a force on the first object. The two forces are equal in strength and oriented in opposite directions. The third law states that for every force there is an equal and opposite force. For example, if you push on a wall, it will push back on you as hard as you are pushing on it.